There have been other methods of thought in the Islamic world, at variance with the illuminationist and peripatetic methods, that have played genuine and basic roles in the development of Islamic culture. Two such methods are 'irfan (gnosis) and kalam (scholastic theology).

Neither the 'urafa' nor the muralallimin have regarded themselves as followers of the philosophers, whether illuminationists or peripatetics. They have taken stands against the philosophers and clashed with them. These clashes have had an appreciable effect on the fate of Islamic philosophy. Irfan and kalam have both motivated Islamic philosophy through conflict and clashes and opened up new horizons for philosophy.

Four Islamic Approaches
Many of the questions Islamic philosophy addresses were first addressed by the mutakallimin or the 'urafa; although they express themselves in a way different from that of the philosophers. Islam comprehends four methods of thought, and Islamic thinkers are of any of four sons. I am discussing methods of thought having a philosophical character in the most general sense, that is, constituting an ontology and a cosmology.

I am treating the universals of philosophy, and not the methods of thought of jurisprudence, exegesis, tradition, letters, politics, or ethics, which are another matter entirely. Each of these methods has taken on a special character under the influence of Islamic teachings and differs from its counterparts outside the Islamic sphere. The particular spirit of Islamic culture governs each.

One method is the deductive method of peripatetic philosophy. It has numerous adherents in history. Most Islamic philosophers, including Al-Kindi, Farabi, Avicenna, Khwaia Nasir ad-Din Tusi, Mir Damad, Ibn Rushd of Andalusia, Ibn Baja of Andalusia, and Ibn as-Sa'igh of Andalusia, have followed this method. The perfect exemplar of this school is Avicenna. Such philosophical works of his as the Kitab ash-Shifa' (The book of healing [the so called Sufficientia]), Isharat va Tanbihat (Allusions and admonitions), Najat (Deliverance), Danishnama-yi Ala'i (The book of knowledge, dedicated to 'Ala ad-Dawla), Mabda' va Ma 'ad (The source and the destination), Ta'liqat-i Mubahathat (Annotations to the discussions), and 'Uyun al-Hikma (Wellsprings of wisdom) are all works of peripateticism. This method relies exclusively on rational deduction and demonstration.

A second method is the illuminationist method. This has fewer adherents than the first method. It was revived by Shihab ad-Din Suhravardi and followed by Quth ad-Din Shirazi, Shahrazuri, and a number of others. Suhravardi is considered the perfect exemplar of this school. He wrote numerous books) including the Hikmar al-lshraq (Wisdom of illumination), Talvihar (Intimations), Mutarahat (Conversations), Muqavamat (Oppositions), and Hayakil anNur (Temples of light). The best known of them is the Hikmat al-Ishraq; only this work is wholly devoted to the illuminationist method. Suhravardi has written some treatises in Persian, among them Avaz-i Par-i Jabra 'ii (The song of Gabriel's wing) and Aql-i Surith (The red intelligence).

The illuminationist method rests on rational deduction and demonstration and on endeavour and purification of the soul. According to this method, one cannot discover the underlying realities of the universe through rational deduction and demonstration alone.

The wayfaring method of 'irfan, or Sufism, is the third method. It relies exclusively on a purification of the soul based on a concept of making one's way to God and drawing near to the Truth. This way is said to culminate in the attainment of Reality. The method of 'irfan places no confidence at all in rational deduction. The 'urafa' say that the deductionists stand on wooden legs. According to the method of ‘irfan, the goal is not just to uncover reality, but to reach it.

The method of 'irfan has numerous adherents, some of whom have grown famous in the Islamk world, including Bayazid Histami, Hallal, Shibli, Junayd of Baghdad, Dhu'n-Nun Misri, Abu Sa'id-i Abi'l-Khayr, Khwaja 'Abdullah Ansari, Abu Talib Makki, Abu Nasr Sarraj, Abu'l-Oasim Qushayri, Muhyi 'd-Din Ibn 'Arabi of Andalusia, Ibn Faridh of Egypt, and Mawlana Rumi. The perfect exemplar of Islamic irfan, who codified it as a science and had a compelling influence on all who followed him, is Muhyi 'd-Din Ibn 'Arabi.

The wayfaring method of 'irfan has one feature in common with the illuminadonist method and two features at variance with it. Their shared feature is reliance on reform, refinement, and purification of the soul. The distinguishing features of each areas follows:

The 'arif wholly rejects deduction; the illuminationist upholds it and uses thought and purification to aid each other. The illuminationist, like any other philosopher, seeks to discover reality; the ‘arif seeks to attain it.

Fourth is the deductive method of kalam. Like the peripatetic, the mutakatlimin rely on rational deduction, but with two differences. First, the principles on which the mutakallimin base their reasoning are different from those on which the philosophers base theirs. The most important convention used by the mutakallimin, especially by the Mu'tazilites, is that of beauty and ugliness.

However, they differ among themselves as to the meaning of this convention: the Mu'tazilites regard the concept of beauty and ugliness as rational, but the Ash'arites regard it as canonical. The Mu'tazilites have derived a series of principles and formulae from this principle, such as the formula of grace and the incumbency of the optimal (wujub-i aslah) upon God Most High.

The philosophers, however, regard the principle of beauty and ugliness as a nominal and human principle, like the pragmatic premises and intelligibles propounded in logic, which are useful only in polemics, not in demonstration. Accordingly, the philosophers call kalam "polemical wisdom," as opposed to "demonstrational wisdom."

Second, the mutakallimin, as opposed to the philosophers, regard themselves as committed, committed to the defence of the bounds of Islam. Philosophical discussion is free; that is, the philosopher has not the predetermined object of defending a particular belief, The mutakallim does have such an object. The method of kalam is subdivided into three methods: the Mu'tazilite, the Ash'arite, and the Shi'ite.

Mu'tazilites are numerous in history. There are Abu'l Hudhayl 'Allaf, Nazzam, Jahiz, Abu 'Ubayda, and Mu'ammar ibn Muthanna, all of whom lived in the second or third centuries of the Hijra. Qazi 'Abd al-Jabbar in the fourth century and Zamakhshari around the turn of the fifth-sixth centuries also exemplify this school.

Shaykh Abu'l-Hasan Ash'ari (d. 330) perfectly exemplifies the Ash'arite school. Qazi Abu Bakr Baqillani, Imam al-Haramayn Juvayni, Ghazali, and EaMir ad-Din Razi all followed the Ash'ari method.

Shi'i mutakallimin are also numerous. Hisham ibn al-Hikam, a companion of Imam Ja'far Sadiq (upon whom be peace) was a Shi'i mutakallim. The Nawbakhti family, an Iranian Shi'i family, produced some outstanding mutakallims. Shaykh Mufid and Sayyid Murtaza 'Alam al-Huda are also ranked among Shi'i mutakallimin. The perfect exemplar of Shi'i kalam is Khwaja Nasir ad-Din Tusi. His Tajrid al-'Aqa 'id (Refinement of beliefs) is one of the most famous works of kalam. He was also a philosopher and mathematician. After him, kalam took a wholly different course and assumed a more philosophical character.

Among the Sunnis' works of kalam, the most famous is the Shark-i Mavaqif (Elucidation of the stations), with text by Qazi 'Azud ad-Din Iji (a contemporary of Hafiz, who praised him in his poetry) and annotations by Sharif Jurjani. This work was deeply influenced by the Tajrid al- Aqa'id.

Sublime Wisdom
The four streams of thought continued in the Islamic world until they reached a point of confluence called "sublime wisdom" (hikmat-i muta ‘aliya). The science of sublime wisdom was founded by Sadr al-Muta'allihin Shirazi (or Mulla Sadra) (d. lO5O/l64o).'~ The term "sublime wisdom" occurs in Avicenna's Isharat, but Avicenna's philosophy never became known by this name.

Mulla Sadra formally designated his philosophy sublime wisdom, and it became so known. His school resembles Suhravardi's in method in seeking to combine demonstration with mystic vision and direct witness, but it differs in its principles and conclusions.

In Mulla Sadra's school, many of the points of disagreement between peripateticism and illuminationism, between philosophy and 'irfan, or between philosophy and kalam have been definitively resolved. Mulla Sadra's philosophy is not a syncretism, however, but a unique philosophical system, that, although the various Islamic methods of thought had an impact on its formation, one must regard as autonomous.

Mulla Sadra has written numerous works, among them the Asfar-arba’a (The four journeys, or books), Ash-Shavahidar-Rububiya (Witnesses to lordship), Mabda 'Va Ma’ad (The source and the destination), ‘Arshiya (On the Empyrean), Masha'ir (The perceptual faculties), and Sharh-i Hidaya-yi Athir ad-Din Abbari (An elucidation of Athir ad-Din Abhari's guidance).

Among Mulla Sadra's followers is Hajj Mulla Hadi Sabzavari (1212/1798-1289/1878), author of the Kitab-i Manzuma (The rhymed book) and the Sharh-i Manzuma (The elucidation of the rhymed book). A typical basic library for study of the ancient sciences might consist of Sabzavari's Shark-i Manzuma, Mulla Sadra's Asfar, Avicenna's Isharat and Shrja', and Suhravardi's Hikmat al-Ishraq.

Mulla Sadra organised the philosophical topics concerning the intellectual and rational way in a manner paralleling the manner in which the 'urafa' had propounded the way of the heart and spirit. The 'urafa hold that the wayfarer accomplishes four journeys in carrying through the method of the ‘arif:

The journey from creation to God. At this stage, the wayfarer attempts to transcend nature as well as certain supernatural worlds in order to reach the Divine Essence, leaving no veil between himself and God.

The journey by God in God. After the wayfarer attains proximate knowledge of God, with His help the wayfarer journeys through His phases, perfections, names, and attributes.

The journey from God to creation by God. In this journey, the wayfarer returns to creation and rejoins people, but this return does not mean separation and remoteness from the Divine Essence. Rather, the wayfarer sees the Divine Essence with all things and in all things.

4. The journey in Creation by God. In this journey, the wayfarer undertakes to guide the people and lead them to the Truth.

Mulla Sadra, considering that philosophical questions constitute a "way," if a mental one, sorted them into four sets:

1. Topics that constitute a foundation or preliminary to the study oft tauhid. These (the ordinary matter of philosophy) constitute our mental journey from creation to God.

2. Topics of tauhid, theology, and divine attributes-The journey by God in God.

3. Topics of the divine acts, the universal worlds of being-the journey from God to creation by God.

4. Topics of the soul and the Destination (ma 'ad)-the journey in creation by God.

The Asfar Arba 'a, which means the Four Journeys, is organised on this basis. Mulla Sadra, who called his special philosophical system sublime wisdom, referred to conventional philosophy, whether illuminationist or peripatetic, as common or conventional philosophy.

Overview of Philosophies and Wisdom’s
Philosophy and wisdom, in the widest sense, are variously classified from different perspectives; but if we consider them from the standpoint of method, they fall under four headings: deductive wisdom₃ experiential wisdom, experimental wisdom, and polemical wisdom.

Deductive wisdom rests on syllogism and demonstration. It has to do only with greater and lesser, result and concomitant, contradictory and contrary, and the like. Experiential wisdom pertains not only to deduction but to experience, inspiration, and illumination. It takes its inspiration more from the heart than from the reason.

Experimental wisdom pertains neither to a priori reasoning and deduction nor to the heart and its inspirations. It pertains to sense, trial, and experiment. It takes the products of the sciences, the fruits of trial and experiment, and, by interrelating them, welds them into wisdom and philosophy.

Polemical wisdom is deductive, but the premises for its deductions are what logicians call common knowledge (mashhurar) and accepted facts (ma qbulat). There are several kinds of premises to deduction, including first axioms (badihiyat) and common knowledge. For instance, the idea that two things each equal to a third are equal to each other, which is expressed in the phrase "the equal to the equal are equal," and the idea that it is absurd for a proposition and its contradictory to hold true at once are considered axiomatic. The idea that it is ugly to yawn in the presence of others is considered common knowledge.

Deduction on the basis of axioms is called demonstration, and deduction on the basis of common knowledge is considered an element of polemics. Therefore, polemical wisdom means a wisdom that deduces global and universal ideas from common knowledge.

The mutakallimin generally base their deductions on the beauty or the ugliness of a thing, on rational beauty and ugliness, so to speak. The hukama' hold that all beauty and ugliness relate to the sphere of human life; one cannot evaluate God, the universe, and being by these criteria. Thus, the hukama' call kalam polemical wisdom.

The hukama believe that the central principles of religion may be better deduced from the premises of demonstration and in reliance on first axioms than from the premises of common knowledge and polemics. In Islamic times, especially among the Shi'a, philosophy, without departing from its mission of free inquiry and committing itself in advance, gradually proved the best source of support for Islamic principles. Accordingly, polemical wisdom, in the hands of such persons as Khwaja Nasir ad-Din Tusi, gradually took on a demonstrational and illuminationistic character. Thus, kalam came to be overshadowed by philosophy.

Although experimental wisdom is extraordinarily valuable, it has two shortcomings. One is that its compass is confined to the experimental sciences, and the experimental sciences are confined to what is sensible and palpable. Man's philosophical needs extend beyond what is in the domain of sense experience. For instance, when we discuss the possibility of a beginning of time, an end to space, or an origin for causes, how are we to find what we seek in the laboratory or under the microscope? Thus, experimental wisdom cannot satiate man's philosophical instinct and must elect silence on basic philosophical questions.

The other shortcoming lies in the fact that the value of experimental questions is rendered precarious by their confinement to and dependence upon nature. Questions of experimental science have a time-bound value and may grow obsolescent at any moment. A wisdom based on experiment is naturally precarious and so does not meet a basic human need, the need for certainty. Certainty arises in questions having mathematical abstraction or philosophical abstraction, and the meanings of mathematical and philosophical abstractions can be clarified only by philosophy.

There remain deductive wisdom and experiential wisdom. The questions discussed in the following sections should elucidate these two wisdom’s and spell out their value.

Problems in Philosophy

Being
Philosophical questions pivot on being. That which is to philosophy what the body is to medicine, number is to mathematics, or quantify is to geometry is being qua being. It is the subject of philosophy and all philosophical topics turn on it. In other words, philosophy has for its subject existence.

Several kinds of questions turn on being. One is questions pertaining to being, or existence, and its opposites in the two respective senses: nonbeing and essence (mahiya). There is nothing but being in the objective world. Being has no opposite outside the mind. But the conceptualising mind of man has formed two concepts vis-a'-vis being or existence: nonbeing and essence (of course, essences). A range of philosophical questions, especially in sublime wisdom, pertains to existence and essence, and another range pertains to being and nonbeing.

A second group of questions pertains to divisions of being. Being in its turn has divisions that are regarded as amounting to species of being; in other words, being is divisible (for instance, into the objective and the subjective, the necessary and the possible, the eternal and the created in time, the stable and the changing, the singular and the plural, the potential and the act, and the substance and the accident). Of course, these are the primary divisions of being, that is, the divisions that enter into being by virtue of the fact that it is being.

To illustrate, divisions into black and white, large and small, equal and unequal, odd and even, or long and short are divisions not in being qua being but in being qua body or in being qua quantifiable. Corporeality in being corporeality, or quantity in being quantity, admits of such division. However, division into singular and plural, or division into necessary and possible, is division of being qua being.

Close research has been done in philosophy as to the criteria for these divisions, what distinguishes the divisions of being qua being from other divisions. Some philosophers have regarded certain divisions as applying to body qua body and thus falling outside the scope of first philosophy, but other philosophers for various reasons have regarded these divisions as applying to being qua being and thus falling under this same domain.

A third group of questions pertains to the universal laws governing being, such as causality, the correspondence of cause and effect, the necessity governing the system of cause and effect, and priority versus synchronism among the levels of being.

A fourth group of questions pertains to demonstration of the planes of being or worlds of being. Being has particular planes or worlds. The hukama' of Islam believe that there are four general worlds or four emergencies (nash'a):

1. The world of nature, or the nasut

2. The world of ideas, or the malakut

3. The world of [separate] intelligence’s, or the jabarut

4. The world of divinity, or the lahut

The world of nasut is the world of matter, motion, and space-time. It is the world of nature and sense objects, this world. The world of [Platonic] ideas [similitude’s], or the malakut, is a world superior to nature, having forms and dimensions, but lacking motion, time, and change.

The world Jabarut is the world of the [separate] intelligence’s or the world of the [abstract] idea (ma'na), free of forms and images and thus superior to the world of malakur. The world of lahut is the world of divinity and unity.

A fifth group of questions pertains to the relations between the world of nature and the worlds above it, the descent of being from lahut to nature, and to the ascent from nature to the higher worlds. With special reference to man, these are called questions of the destination (ma 'ad) and figure very prominently in sublime wisdom.

Existence and Essence
Is existence substantive, or is essence? We always distinguish two valid senses in which things may be spoken of: the isness of a thing and the whatness of a thing. For instance, we know that man is, the tree is, number is, and quantity is, but number has one whatness, one essence, and man has another. If we ask, "What is number?" we receive one answer. If we ask, "What is man?" we receive another.

Many things have a patent isness; that is, we know that they are. But we may not know what they are. For instance, we know that life is or that electricity is, but we may not know what life is or what electricity is. We know what many things are-for instance, we have a clear definition of a circle and so know what a circle is-but we do not know whether the circle exists in objective nature. Thus, isness is something other than whatness.

This plurality, this dichotomy of essence and existence, is purely subjective. In extensional reality, no thing is twofold. Therefore, one of these two is objectively so and substantive, and the other is nominal and not substantive.

The whole question of existentialism versus essentialism has no ancient historical antecedents. This topic originated in the Islamic world. None of the early philosophers, Farabi, Avicenna, Khwaja Nasir ad-Din Tusi, or even Suhravardi, discussed anything under this heading. The topic made its debut in philosophy in the time of Mir Damad (the beginning of the eleventh century of the Hijra. Mir Damad was an essentialist. However, his famous pupil, Mulla Sadra, made a compelling case for existentialism, and from then onward, every philosopher of note has been an existentialist. In the third volume of UsuI-i Falsafa va Ravish-i Ri'azism, I have discussed the respective ideas of the 'urafa', the mutakallimin, and the philosophers as precursors to this philosophical conception of Mulla Sadra's.

Another philosophy sometimes known as existentialism has flourished in our own time. This form of existentialism pertains to man and has reference to the idea that man, by contrast with all other beings, has no definite, preassigned essence and no form determined by nature. Man designs and builds his own whatness.

This idea is largely correct and supported by Islamic philosophy, except that, what in Islamic philosophy is called existentialism does not apply to man alone, but to the whole universe, and, second, when we speak of existentialism or isalat-I vujud in an Islamic context, we are using the term isalat (-ism) in its sense of substantive reality or objective being, as opposed to nominal or mental existence. When we use it in the Western context of modern existentialism, we are using it in its sense of primacy or priority. One should by no means conflate the two senses.

The Objective and the Subjective
A thing is either objective or subjective. Objective being means being external to and independent of man's mind. We know, for instance, that mountain, sea, and plain have being external to our minds and independent of them. Whether our minds conceive of them or not, indeed, whether ourselves and our minds exist or not, mountain, sea, and plain exist.

But that mountain, sea, and plain have an existence in our minds as well. When we imagine them, we give them being in our minds. The being things find in our minds is called subjective being or mental being.

Two questions arise here. One is why the images of things appearing in our minds should be conceived of as a kind o fbeing for those things in our minds. If they are, one might say that the image of a thing painted on a wall or printed on a sheet of paper deserves to be called another kind of being, a parietal being or a papyraceous being. If we term mental images a form of being for the thing imagined, to be just, we have employed a metaphor and not spoken the literal truth, but philosophy ought to deal with the literal truth.

The relation of a mental form to an external object (for instance, the relation of a mental mountain or sea to an external mountain or sea) is far more profound than the relation of the picture of a mountain or a sea on a sheet of paper or a wall to that external mountain or sea. If what appears in the mind were only a simple image, it would never give rise to consciousness, just as the image on the wall does not give rise to consciousness in the wall. Rather, the mental image is consciousness itself.

The other question is whether mental being, as a concept actually relating to man and the human psyche, belongs to the realm of psychology. Philosophy deals with general questions, and such particular questions pertain to the sciences.

Philosophers have demonstrated that we are conscious of external objects because our mental images, far from being simple, area kind of realisation of existence in our minds for the essences (mahiya) of the objects. Although from one standpoint, the question of mental images is a question of the human psyche and so belongs to the field of psychology, from another standpoint, that man's mind is in fact another emergence (nash'a) of being, resulting in being in its essence taking two forms, subjective and objective, it is a question for philosophy.

Avicenna and Mulla Sadra have said (the former allusively, near the beginning of the "Ilahiyat" of his Shifa’ and the latter explicitly and at length in his commentary to the same work) that at times a question may pertain to two different disciplines from two standpoints; for instance, a question may pertain to philosophy from one standpoint and to the natural sciences from another.

Truth and Error
The question of mental being bas another angle that has been studied: It has to do with the validity of perceptions, the extent to which our perceptions, sensations, and conceptions of the external world are valid. From ancient times, philosophers have asked whether what we perceive of an object by means of our senses or our reason corresponds to actuality, the thing in itself.

Some postulate that some of our sense perceptions or rational perceptions do correspond to actuality, the thing in itself, and some do not. Those that correspond to actuality are termed "truth," and those that do not are termed "error." Sight, hearing, taste, touch, and smell are all subject to error. But most of our sense perceptions correspond fully to reality. Through these same senses, we accurately distinguish night from day, far from near, large from small in volume, tough from smooth, and cold from hot.

Our reason is likewise subject to error. Logic was compiled to avert errors of the reason in its deductions. But most of our rational deductions are valid. When we add up all the debits and all the credits in a ledger and subtract the former from the latter, we are performing a mental and rational procedure that we are perfectly assured will hold true if we are sufficiently careful and exact.

However, the Sophists of Greece denied the distinction between truth and error. They said that whatever some person feels and thinks is for that person the truth. They said that man is the measure of all things. They radically denied reality and, having denied it, left nothing in corresponding to which man's perceptions and sensations could be true and in failing to correspond to which they could be erroneous.

The Sophists were contemporaries of Socrates (Socrates came along near the close of the Sophist period). Protagoras and Gorgias are two famous Sophists. Socrates, Plato, and Aristotle rebelled against them.

After Aristotle's time, another group appeared in Alexandria, called the Sceptics, the most famous of whom is Pyrrho. The Skeptics did not deny actuality in principle but denied that human perceptions correspond to it. They said that one perceives an object in a certain way under the influence of internal states and certain external conditions. Sometimes two people experiencing different states or viewing from different angles will seethe same event in two different ways. A thing may appear ugly in one's eyes and beautiful in another's, or single in one's eyes and double in another's. The air may feel warm to one and cold to another. A flavor may taste sweet to one and bitter to another. The Skeptics, like the Sophists, denied the validity of knowledge.

Bishop Berkeley wholly rejects external reality. No one has been able to refute his reasons for his position, although everyone knows they are fallacious.

Those who have sought a reply to the ancient Sophists exemplifled by Berkeley have not taken the approach that could resolve the sophism. The philosophers of Islam have held that the basic approach to resolving this sophism consists in our perceiving the reality of mental being. Only thus is the puzzle solved.

In approaching mental being, the hukama of Islam first define knowledge, or perception, as consisting in a kind of being for the oblect perceived within the being of the perceiver. They go on to cite certain demonstrations in support of this position, and then they recount and reply to certain objections to mental being or allegations of problems in it.

This topic did not exist in this form early in the Islamic period and afortiori did not exist in Hellenic times. Nasir ad-Din Tusi was the first to speak of the objective and the subjective in his works of philosophy and kalam. Thereafter, it came to occupy a major place in the works of such comparatively recent philosophers as Mulla Sadra and Mulla Hadi Sabzavari. Farabi, Avicenna, and even Suhravardi, as well as their followers, never broached the subject of mental being or even used the term in their works. The term first appeared after Avicenna's time.

However, what Farabi and Avicenna said on other subjects shows that they believed perception to consist of a simulacrum of the reality of the object perceived within the being of the perceiver. But they neither sought to demonstrate this point nor conceived of it as an independent question of being, an independent division of being.

The Created in Time and the Eternal
The Arabic word hadith has the lexical and customary meaning of new, and qadim means old. However, these words have other meanings in the terminologies of philosophy and kalam. Like other people, when philosophers speak of the hadith and the qadim, they seek to know what is new and what is old, but in speaking of a thing as new, they mean that before it was, it was not-that is, that first it was not, then it was. In speaking ofa thing as old, they mean that it always has been and never was not. Suppose there is a tree that has lived for billions of years. In common usage, it would be spoken of as old, quite old indeed, but according to the terminologies of philosophy and kalam, it is hadith (new) because there was a time billions of years ago when it was not.

Philosophers define createdness in time (huduth) as the precedence of a thing's nonbeing to its being, and they define eternality (qidam) as the nonprecedence of a thing's nonbeing to its being. Therefore, an entity is created in time whose nonbeing precedes its being, and an entity is eternal for which no nonbeing prior to its being can be conceived.

Discussion of the question of the created in time and the eternal turns on this point: Is everything in the universe created in time and nothing eternal, such that whatever we consider first was not and then was? Or is everything eternal and nothing created in time, such that everything has always been? Or are some things created in time, and some eternal, such that, for instance, shapes, forms, and externals are created in time, but matter, subjects, and invisible things are eternal? Or are individuals and parts created in time, whereas species and wholes are eternal? Or are natural and material phenomena created in time, whereas abstract and suprameterial phenomena are eternal? Or is only God, the Creator of the whole and Cause of causes, eternal, whereas all else is created in time? Overall, is the universe created in time, or is it eternal?

The mutakallimin of Islam believe that only God is eternal. All else-matter and form, individuals and species, parts and wholes, abstract and material-constitutes what is called the world or 'other' (masiva) and is created in time. The philosophers of Islam, however, believe that createdness in time is a property of the material world, whereas the supernatural worlds are abstract and eternal. In the world of nature, too, principles and universals are eternal, whereas the phenomena and particulars are created in time. Therefore, the universe is created in time with respect to its phenomena and particulars but eternal with respect to its principles and universals.

Debate over createdness in time and eternality has excited acrimonious disputes between the philosophers and the mutakallimin. Abu Hamid Ghazali, who, although leaning to 'irfan and Sufism in most of his works, leans to kalam in some, declares Avicenna an unbeliever for his stand on several questions, among them his belief in the eternality of the world. In his famous Tahajut al-Falsafa (The incoherence of the philosophers), Ghazali has criticised philosophers on twenty points and exposed what he believed to be the incoherencies in their thought. Ibn Rushd of Andalusia has rebutted Ghazali in Tahajut at- Tahafut (The incoherence of the "incoherence").

The mutakallimin say that if a thing is not created in time but eternal-if it has always been and never not been-then that thing has no need of a creator and cause. Therefore, if we suppose other eternal things exist than the Essence of the Truth, it follows that they will have no need of a creator and so in reality be necessary beings in their essence, like God, and the demonstrations that show the Necessary Being in Essence to be singular do not permit us to profess more than one such Necessary Being. Accordingly, no more than one Eternal Being exists, and all else is created in time. Therefore, the universe is created in time, including the abstract and the material, principles and phenomena, species and individuals, wholes and parts, matter and form, visible and invisible.

The philosophers have rebutted the arguments of the mutakallimin decisively, saying that all the confusion turns on one point, which consists in supposing that, if a thing has a continuous existence into the indefinite past, it has no need of a cause, whereas this is not so. A thing's need or lack of need for a cause pertains to its essence, which makes it a necessary being or a possible being; it has nothing to do with its createdness in time or eternality. By analogy, the sun's radiance stems from the sun and cannot exist apart from it. Its existence depends on the sun's existence. It is the sun's luminance and issues from the sun whether we suppose there was a time this radiance did not exist or we suppose it has always existed, along with the sun. If we suppose that the sun's radiance has coexisted with the sun itself from preeternity to posteternity, this does not entail its having no need of the sun.

The philosophers maintain that the relation of the universe to God is as the relation of the radiance to the sun, with this difference: The sun is not conscious of itself or of its action and does not perform its function as an act of will; the contrary is true of God.

At times we encounter expressions in the primary texts of Islam that compare the relation of the universe and God to the relation of radiance and the sun. The noble verse of the Qur'an states, "God is the Light of the heavens and the earth" (24:35). Exegetes have interpreted this verse to mean that God is the light-giver of the heavens and the earth (that the being of heaven and earth is a ray of God).

The philosophers do not adduce any evidence for the eternality of the universe from the universe itself; rather, they approach this argument from the position that God is the Absolutely Effulgent and the Eternally Beneficent-we cannot possibly conceive of His effulgence (emanation) and beneficence as limited, as terminating somewhere. In other words, the theistic philosophers have arrived at the eternality of the universe through an a priori demonstration, that is, by making the being and attributes of God the premise to the eternality of the universe.

Generally, those disbelieving in God advance the position of the eternality of the universe, but the theistic philosophers say that the same thing nonbelievers adduce as a reason for God's non-existence in their view implies God's existence. The eternality of the universe is a hypothesis to nonbelievers, but it is an established fact to theistic philosophers.

The Mutable and the Constant
Change means transformation and constancy means uniformity. We continually witness changes in the universe. We ourselves continually make transitions from state to state, from period to period, beginning when we are born and ending when we die. The same holds for earth and sea, for mountains, trees, animals, stars, solar systems, and galaxies. Are these changes outward, pertaining to the configuration, form, and accidents of the universe, or are they profound and fundamental, such that no constant phenomenon exists in the universe? Are the changes that occur in the universe transient and instantaneous, or are they gradual and protracted?

These questions, too, date from remote times; they were discussed in ancient Greece. Democritus, known as the father of the atomic theory and also as the laughing philosopher, maintained that all change or transformation is superficial because natural being is based on atomic particles, which are forever in one state and unchangeable. The changes we witness are like those in a heap of gravel, massed sometimes in one shape, sometimes in another, but never changing in identity or real nature. This is the mechanistic outlook and constitutes a kind of mechanistic philosophy.

Another Greek philosopher, Heraclitus, maintains that nothing remains in the same state for two successive instants. As he says, you cannot set foot twice in the same river because at the second instant you are not who you were before and that river is not the same river. This philosophy stands opposite to Democritus's in seeing everything in a state of flux and inconstancy, but it says nothing contrary to mechanism; that is, it advances no idea of dynamics.

Aristotle's philosophy has no quarrel with the idea that all the parts of nature change, but undertakes to determine which changes are gradual and protracted and which are transient and instantaneous. It terms the gradual changes "motion" and the transient changes "generation and corruption" (that is' a transient coming into being is called generation, and a transient extinction is called corruption). Because Aristotle and his followers consider the basic changes occurring in this world, especially those that appear in substances, as transient, they term this "the world of generation and corruption."

At other moments, constancy obtains. If we regard changes as transient, because they occur in an instant, although at other instants or through time things are constant, such mutable things have a relative mutability and a relative constancy. Therefore, if change is in the mode of motion, it is absolute change. If it is in the mode of generation and corruption, if it is in an instantaneous mode-it is relative.

According to the Aristotelians, although nothing absolutely constant and uniform exists in nature, but everything is mutable (contrary to the view of the Democriteans), because substances are basic to nature and changes in substances are transient, the world has a relative constancy along with relative change. But constancy governs the world to a greater extent than does change.

Aristotle and the Aristotelians regard all things as falling under ten basic generic classes, which they call the ten categories: substance, quantity, quality, determination in space, position, determination in time, relation, condition, action, and passion.

Motion occurs only in the categories of quantity, quality, and determination in space. In all other categories change is transient; in other words, all other categories enjoy a relative constancy. Even those three categories in which motion occurs-because the motion is intermittent-are governed by a relative constancy. Therefore, in Aristotle's philosophy, one encounters more constancy than change, more uniformity than transformation.

Avicenna believed that motion occurs in the category of position as well. He demonstrated that certain motions, such as the rotation of the earth about its axis, constitute a positional motion, not a motion in spatial determination. Thus, after Avicenna, motion in spatial determination was restricted to transferential motion. Avicenna did not demonstrate the existence of a new sort of motion, but reclassified as positional what had previously been categorised as a motion in spatial determination. His reclassification is generally accepted.

Mulla Sadra effected a major transformation in Islamic philosophy by demonstrating substantial motion. He demonstrated that, even on the basis of the Aristotelian principles of matter and form, we must accept that the substances of the world are in continuous motion; there is never so much as an instant of constancy and uniformity in the substances of the world. The accidents (that is, the nine other categories), as functions of the substances, are also in motion. According to Mulla Sadra, nature equals motion, and motion equals continuous, uninterrupted creation and extinction.

Through the principle of substantial motion, the visage of the Aristotelian universe is wholly transformed. According to this principle, nature, or matter, equals motion. Time consists in the measure or tensile force of this substantial motion, and constancy equals supernatural being. What exists consists of, on the one hand, absolute change (nature) and, on the other, absolute constancy (the supernatural). The constancy of nature is the constancy of order, not the constancy of being; that is, a definite, immutable system governs the universe, and the contents of the system are all mutable (they are change itself). Both the being and the system of this universe stem from the supernal. Were it not for the governance of the other world, this world, which is wholly flux and mutation, would be cut off from its past and future. "Many times has the water exchanged in this stream,/Still the moon's and the stars' reflections remain."

Prior to Mulla Sadra, the topic of the mutable and the constant was felt to belong to the natural sciences, in that any determination or any division that applies to a body qua body belongs to the natural sciences. It was said that it is such-and-such a body that is either constant or mutable, or that is either still or in motion. In other words, motion and stasis are among the accidents of a body. Therefore, the topic of the constant and the mutable ought to fall wholly within the domain of the natural sciences.

This all changed with Mulla Sadra's realisation of existentialism (the substantive reality of being), his realisation of substantial motion, and his demonstration that the natures of the universe constitute the mob ik qua mobile and the mutable qua mutable (that is, that a body is not something to which motion is merely added as an accident, whereby at times this motion can be annulled, leaving the motionless state we call stasis). Rather, the natures of the universe are -motion itself, and the contrary of this substantial motion is constancy, not stasis.

Stasis holds for the accidental motions the state of whose absence we call stasis but is inconceivable in the case of essential, substantial motion. The contrary of this substantial motion that is the substance itself consists of substances for which constancy is the very essence. These are entities beyond space and time, devoid of spatiotemporal forces, potentialities, or dimensions. Therefore, it is not the body that is either constant or mutable. Rather, it is being qua being that appears either as constancy itself (as supramaterial beings) or as continuous flux/becoming/creation itself (the world of nature). Therefore, just as being is in its essence divisible into necessary and possible, so is it in its essence divisible into the constant and the fluid.

Thus, according to Mulla Sadra, only certain kinds of motions the accidental motions of a body having stasis is for their opposite-ought to be studied under the heading of the natural sciences. Other motions, or indeed these very motions when not regarded from the standpoint of their being accidents of natural bodies, ought to be discussed and studied in first philosophy. Mulla Sadra himself brought in his discussions of motion under "general phenomena" in the Asfar in the course of discussing potentials and acts, although it warranted a chapter to itself.

Among the key conclusions arising from this great realisation-basically, that being in its essence is divisible into the constant and the fluid and that constant being is one modality of being, while fluid being is another-is that becoming is precisely a plane of being. Although, nominally speaking, we may regard becoming as a synthesis of being and nonbeing, this synthesis is actually a kind of notion or metaphor.

In truth it is the realisation of the substantive reality of being and of the nominal status of essences (mahayat) that permits us to perceive this key reality. Without a grasp of the substantive reality of being, neither a conception of substantial motion nor a conception that flux and becoming are precisely a plane of being would be possible.

Motion has recovered its proper place in the modern philosophy of Europe by other avenues. Some philosophers came to believe that motion is the cornerstone of nature, that nature equals becoming. However, because this idea was not based on existentialism (the substantive reality of being) and the primary division of being into the constant and the fluid, these philosophers supposed that becommg was the same union of opposites that the ancients had deemed absurd. They likewise supposed that becoming falsified the principle of identity (huhuya), which the ancients had taken for granted.

These philosophers said that the presiding principle in the thought of the ancients was the principle of constancy and that, in deeming beings constant, the ancients had supposed that either being or nonbeing must hold sway over things. Therefore, one alone of these holds true (the principle of the impossibility of union and cancellation of opposites). That is, either there is always being or there is always nonbeing; no third alternative obtains. Similarly, because the ancients thought things constant, they supposed of everything that is itself (the principle of identity). But with the realisation of the principle of motion and change in nature, the realisation that nature is continually in a state of becoming, the two principles are groundless because becoming is a union of being and nonbeing; where a thing is both being and non-being, becoming has been demonstrated.

A thing in a state of becoming both is and is not; at every instant, its self is its not-self; its self’s at once its self and not its self; the self of its selfis progressively negated. Therefore, if the principle governing things were that of being and nonbeing, both the principle of the impossibility of the union of opposites and the principle of identity would hold true. Because the principle governing things is the principle of becoming, neither of these other principles holds true.

The principle of the impossibility of the union of opposites and the principle of identity, which held unrivalled sway over the minds of the ancients, arose from a further principle that they also accepted implicitly: the principle of constancy. As the natural sciences showed the invalidity of the principle of constancy, these two principles, too, lost their credibility. This development represents the conception of many modern philosophers, from Hegel onward.

Mulla Sadra invalidated the principle of constancy by other means. Motion, according to his realisation, implies that nature equals inconstancy and constancy equals abstraction. Unlike the modern philosophers, however, he never concludes that because nature equals flux and becoming, the principle of the impossibility of the union and cancellation of opposites is falsified. Although Mulla Sadra regards becoming as a kind of union of being and nonbeing, he does not treat this as a union of opposites because he has realized a more important principle: that being is divisible in its essence into the constant and the fluid. Constant being is a plane of being, not a synthesis of being and nonbeing. The synthesis of becoming from being and nonbeing is not a union of two opposites just as it is not the negation of the self of a thing.

The modern philosophers' confusion has two roots: their failure to perceive the division of being into the constant and the fluid and their inadequate conception of the principles of contradiction and contrariety.

Cause and Effect
The most ancient of philosophical questions is that of cause and effect. The concept of cause and effect appears in every philosophical system, unlike such concepts as existentialism and subjective being, which have a prominent place in some philosophies and pass unnoted in others, the concept of potential and act, which plays an important role in Aristotelianism, or the concept of the constant and the mutable, which has a deservedly prominent position in the philosophy of Mulla Sadra.

Causation is a kind of relation between two things, one of which we call the cause and the other, the effect. This is the most profound of relations. The relation of cause and effect consists in the cause's giving being to the effect. What the effect realises from the cause is its whole being, its whole reality; therefore, if the cause were not, the effect would not be. We find such a relation nowhere else. Therefore, the effect's need of the cause is the keenest of needs, a need at the root of being. Accordingly, if we would define cause, we must say, "A cause is that thing an effect needs in its essence and being."

Every phenomenon is an effect, and every effect needs a cause; therefore, every phenomenon needs a cause. That is, if a thing is not being itself in its essence-if it has appeared as an accident, a phenomenon-it must have arisen through the intervention of a factor we call a cause. Therefore, no phenomenon is without a cause. The hypothesis contrary to this theory is that a phenomenon may appear without a cause. This hypothesis is called coincidence (sudja) or chance (ittrfaq). The philosophy of causality radically rejects this hypothesis.

Philosophers and mutakallimin concur that every phenomenon is an effect and needs a cause, but the mutakallinun define such a phenomenon as created in time (hadith), and the philosophers define it as possible (manikin). That is, the mutakallimin say that whatever is created in time is an effect and needs a cause, and the philosophers say that whatever is possible is an effect and needs a cause. These two definitions lead to the different conclusions previously discussed in "The Created in Time and the Eternal."

A certain cause produces only a certain effect, and a certain effect proceeds only from a certain cause. There are special relations of dependence among the beings of the universe such that any one thing cannot necessarily give rise to any other thing and any one thing cannot necessarily arise from any other thing. We rely on this truth in our everyday experience. For instance, eating is the cause of satiety, drinking water is the cause of quenching of thirst, and study is the cause of literacy. Therefore, if we wish to realise any of these qualities, we have resort to the appropriate cause. For instance, we never drink water or study for the sake of satiety, nor do we consider eating sufficient for the attainment of literacy.

Philosophy demonstrates that such a clear relation obtains among all the processes in the universe. It makes this point through this definition: A unique correspondence and symmetry govern every single cause-and-effect relation and appear in no other such relation. This is the single most important principle in giving order to our thought and in presenting the universe to our thought not as a chaotic aggregate in which nothing is conditional upon anything else but as an ordered, systematic cosmos in which every part has a special place, in which no one thing can displace another.

There are four kinds of cause in the philosophy of Aristotle: the efficient cause, the final cause, the material cause, and the formal cause. These four causes are well illustrated in human industry: If we build a house, the builder or workman is the efficient cause; to dwell in that house is the final cause; the building materials are the material cause; and the configuration of the house, in being appropriate to a dwelling and not, say, to a granary, a bathhouse, or a mosque, is the formal cause. In Aristotle's view, every natural phenomenon, whether a stone, a plant, or a human being, has these same four causes.

Cause as defined by natural scientists differs somewhat from cause as defined by theologians. In theology, or what we now call philosophy, cause means giver of existence. Philosophers call what brings something into existence its cause. Otherwise they do not call it cause, although they may at times call it contributory (mu 'idd). The natural scientists, however, use the word "cause" even where the relation between two things is simply one oftransfer of momentum. Therefore, in the natural scientists' terminology, the builder is the cause of the house in being the point of issue for its construction, through a series of transfers of materials. The theologians, however, never call the builder the cause of the house, in that he does not bring the house into being. Rather, the materials for the house existed beforehand, and the builder's work has been confined to organizing them. Likewise, according to the natural scientists, the relation of mother and father to child is causal; but according to philosophy, it is that of an antecedent, a contributory factor, or a channel, not that of a cause.

The sequence of causes (causes in the terminology of the philosophers, not that of the natural scientists, that is, causes of being, not causes of motion) terminates. It is absurd that it should be interminable. If the being of a thing proceeds from a cause, arises from a cause, and if the being of that cause arises from a further cause, and if the being of that cause arises from a yet further cause, this process could go on through thousands, millions, billions of causes and more. However, it must finally terminate in a cause that arises through its own essence and not through another cause. Philosophers have often demonstrated that an endless regress of causes is absurd, which phrase they shorten to a regress of causes is absurd or usually even further to regress is absurd.

The word tasalsul (regress) is derived from the word silsila (sequence, series, range), with the root meaning of chain. Therefore, tasalsul means an endless chain of causes. Philosophers thus liken the ordered system of causes and effects to a chain whose links interlock in sequence.

The Necessary, the Possible, and the Impossible
Logicians say that if we attribute a predicate to a subject, if, for instance, we say a is b, the relation of 6 to a will have one of three qualities. First, it may be necessary, that is, certain, inevitable, and inviolable; in other words, reason may refuse to accept anything contrary to it. Second, the opposite may be true. That is, the relation may be impossible, meaning it is absurd that the predicate should be an accident of the subject. In other words, reason refuses to accept that it should be one.

Third, the relation may be such that it may be affirmed or negated; that is, it is susceptible both to affirmation and to negation. In other words, reason refuses to accept neither this relation nor its contrary.

For instance, if we consider the relation of the number four to evenness, we see that it is necessary and certain. Reason refuses to accept its contrary. Reason says that the number four is certainly and necessarily even. Therefore, necessity governs this relation.

But if we say that the number five is even, this relation is impossible. The number five has no possibility of being even, and our reason in perceiving this relation rejects it. Therefore, impossibility and inconceivability govern this relation.

But if we say that today the weather is sunny, this is a possible relation. That is, the nature of the day does not require that the weather be sunny or that it be cloudy. Either may accord with the nature of the day. Possibility governs this relation.

It follows that, whatever subject and whatever predicate we consider, their relation will not be devoid of these three qualities, which at times from a certain standpoint we term the three modalities. I have described the logicians' approach.

The philosophers, who study being, say that any idea or concept we consider, take as a subject, and predicate being of will fall under one of these three categories. The relation of being to that idea or concept may be necessary; that is, that thing must necessarily exist. We then call that thing a necessary being.

God is discussed in philosophy under the heading of proofs for necessary being. Philosophical demonstrations show that there is a Being for which nonexistence is absurd and existence is necessary.

If the relation of being to that idea is impossible, that is, if it is absurd that it should exist, we call it an impossible being. An example is a body that is at once spherical and cubical.

If the relation of being to that idea is possible, that is, if that idea is an essence for which reason rejects neither the existence nor the nonexistence, we call it a possible being. All the beings in the universe, in appearing and then disappearing according to a sequence of causes, are possible beings.

Every possible being in itself becomes a necessary being through its cause, but a being necessary through other, not a being necessary in itself. That is) whenever all the causes and preconditions for a possible being exist, it must exist and so becomes a being necessary through other. If it does not come into existence-if so much as one of its preconditions or one of the elements of its causal nexus is lacking-it becomes a being impossible through other.

The philosophers accordingly say that as long as a thing is not necessary, it does not exist. That is, until the existence of a thing reaches the stage of necessity, it will not come into being. Therefore, whatever comes into being does so according to necessity, within a definite and inviolable system. Thus, the system governing the universe and all that is in it is a necessary, certain, and inviolable system. In the language of modern philosophers, it is a determinate system.